added a CRC calculator

[dvtushar]

Issue Id you have worked upon -

501

Briefly explain your program logic -

The calculator uses a simple XOR-based algorithm for a 16-bit CRC. Users can enter input data in hexadecimal format, click the "Calculate CRC" button, and the calculated CRC result is displayed below the button.

Screenshots(Attach 2 screenshots of your own input and output) -

By raising this PR I affirm that -

• [x] My code follows the guidelines of this project.
  

• [x] I have performed a self-review of my own code.
  

• [x] I have commented my code.
  

• [x] My code gives the correct output.
  

• [x] I affirm that I strictly follow contributing guidelines and code of conduct.

[Vedansh-Keshari]

Congratulations 🎉 @dvtushar on your contribution. Thanks for adding value to this repository. 😊

Let's celebrate this fest 😃 by providing more developers 👨‍💻👩‍💻 an opportunity to contribute. Help us make this repository reach far and more by sharing this to your friends and colleagues.

Your efforts can make difference.